Alpha-tocopherol (Vitamin E) acts as a chain-breaking antioxidant in cell membranes. After it neutralizes a lipid peroxyl radical, it is regenerated by which water-soluble antioxidant?
- A Glutathione
- B Uric acid
- C Ascorbate (Vitamin C) ✓
- D Beta-carotene
Correct answer: C. Ascorbate (Vitamin C)
Explanation
When Vitamin E donates a hydrogen atom to a lipid peroxyl radical, it becomes a tocopheroxyl radical. Ascorbate in the aqueous phase donates an electron to regenerate Vitamin E, forming the ascorbyl radical. Glutathione primarily reduces dehydroascorbate, not directly tocopherol radicals.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.